Submission #985047

#	Time	Username	Problem	Language	Result	Execution time	Memory
985047		kim	Cyberland (APIO23_cyberland)	C++17	44 / 100	623 ms	9304 KiB

cyberland

#include "cyberland.h"
#include<bits/stdc++.h>
using namespace std;
using db=double;
using pii=pair<int,int>;
using ll=long long;
#define eb emplace_back
#define f first
#define s second
const db eps=1e-14;

using A=pair<int,db>;
using B=pair<A,int>;
struct cmp{
    bool operator()(const B &l,const B &r)const{
        if(l.f.f!=r.f.f) return l.f.f>r.f.f;
        return l.f.s-r.f.s > eps;
    }
};

vector<pii> adj[100005];
A d[100005];
priority_queue<B,vector<B>,cmp> pq;
queue<int> q;
bitset<100005> vis;

double solve(int N, int M, int K, int H, std::vector<int> U, std::vector<int> V, std::vector<int> W, std::vector<int> arr) {
    for(int i=0;i<N;++i) adj[i].clear();
    for(int i=0;i<M;++i) adj[U[i]].eb(V[i],W[i]), adj[V[i]].eb(U[i],W[i]);
    q.emplace(0);
    vis.reset();
    vis[0]=1;
    while(!q.empty()){
        int u=q.front(); q.pop();
        if(u==H) continue;
        for(auto &[v,w]:adj[u]){
            if(!vis[v]) vis[v]=1, q.emplace(v);
        }
    }
    if(!vis[H]) return -1;


    function<void(db)> dijk=[&](db lim){
        while(!pq.empty()) pq.pop();
        pq.emplace(A(0,0),0);
        d[0]={0,0};
        for(int i=1;i<N;++i){
            if(vis[i]&&arr[i]==0) pq.emplace(A(0,0),i), d[i]={0,0};
            else d[i]={1e9,0};
        }
        while(!pq.empty()){
            auto [w,u]=pq.top(); pq.pop();
            if(u==H) continue;
            for(auto &[v,vw]:adj[u]){
                A w2={w.f,w.s+vw};
                if(arr[v]==2 && w2.s-lim>eps) ++w2.f, w2.s/=2;
                if(d[v].f>w2.f || d[v].f==w2.f&&d[v].s-w2.s>eps){
                    d[v]=w2;
                    pq.emplace(w2,v);
                }
            }
        }
    };

    db l=0,r=1e14;
    while(r-l>eps){
        db mid=(l+r)/2;
        dijk(mid);
        if(d[H].f>=K) l=mid;
        else r=mid;
    }
    dijk(l);
    return d[H].s;
}

Compilation message (stderr)

cyberland.cpp: In lambda function:
cyberland.cpp:57:47: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   57 |                 if(d[v].f>w2.f || d[v].f==w2.f&&d[v].s-w2.s>eps){
      |                                   ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 5
• Subtask 2: 8 / 8
• Subtask 3: 13 / 13
• Subtask 4: 0 / 19
• Subtask 5: 7 / 7
• Subtask 6: 16 / 16
• Subtask 7: 0 / 29
• Subtask 8: 0 / 3